Sometimes that's an indicator that you're studying something you're not talented at. It can be a wakeup call to change to something else.
If this class is required for what you really want, then you need to get a tutor. Talk to the instructor and get some contacts with people who took the class last semester or so.
Also, do the extras, if you have the time. E. g. if there is an optional book, read it. Extra credit? Do it. Yes, it's more work in an area you're not doing so well in, but these things can help you.
But first, talk to your instructor about getting a tutor. There is no shame in getting some help.